With the invertebrate and fish distribution surveys largely completed, and the sea urchin video behaviour project underway, it was time to commence our biodiversity collections. The reasons for making these collections are two-fold. First, we know there are many species yet to be discovered in the coastal waters around the Kermadec Islands. Second, we are wanting to better understand the connections and similarities between the Kermadec Islands, the New Zealand mainland to the south and the South Pacific Islands to the north.
Today we worked on the Napier and Dayrell Islands. The sea conditions generally mean that it is not possible to dive at these sites. However, the weather is so settled at the moment that we took the opportunity to dive at these exposed islands. On dropping into the ocean this morning we were greeted by a couple of inquisitive Galapagos sharks and a very curious grouper.
One of the really unique things that we are experiencing at Raoul Island is that the soundtrack to every dive is the haunting sound of humpback whale song. These whales are everywhere at the moment! If you take the time underwater to slow down your breathing and reduce the sound of spent air bubbling out of your regulator, you can tune in to the squeaks, groans and grunts of these migrating whales.
The day’s work was a success. We collected corals, algae, urchins and sponges. There were also a number of surprise bonus hitchhiker specimens hiding in amongst the red algae that Tom brought back to the Braveheart. These included decorator crabs and miniscule sea hares and skeleton shrimp. These were so well camouflaged that they were only discovered as the algae was being placed on blotting paper to be pressed and dried.